William MacDowell murdered his lover Renee MacRae and their three-year-old son near Inverness in 1976

A married man who murdered his lover and their young son more than 45 years ago will die behind bars.

William MacDowell was sentenced to life in prison with a recommendation that he serve a minimum of 30 years for killing Renee and Andrew MacRae in November 1976.

Police have never found the bodies of the 36-year-old mother or her son, three, with officers now urging the killer to disclose what he did with them so they can be “provided with the dignity they deserve”.

Passing sentence after MacDowell, of Penrith, Cumbria, was found guilty of murder at the High Court at Inverness, judge Lord Armstrong, told him: “These murders appear to have been premediated, planned and carried out in the most calculated way – not a spontaneous event or spur of the moment.”

He added: “These appear, in effect, to have been executions.

“You murdered your victims and then disposed of their bodies and personal effects, including the boy’s pushchair.

“You then took steps to conceal the crimes you had committed.”

As well as being convicted of the murders of Renee and Andrew MacRae, MacDowell was also found guilty of attempting to defeat the ends of justice by disposing of their bodies and personal effects.

Mrs MacRae’s sister, Morag Govans, said afterwards: “More than 45 years of the pain of losing Renee and Andrew doesn’t ease.

“Not a day passes when both are not in our thoughts.”